1. Field of the Invention
The present invention pertains to a multi-disk clutch arrangement, especially to a dual clutch arrangement comprising at least two clutch areas, each with a pressure plate which is connected to a housing for rotation in common around an axis of rotation and which can be shifted in the axial direction with respect to the housing and a clutch disk, the friction surface arrangement of which can be clamped between the pressure plate and an opposing support arrangement, where each of the clutch disk is designed to be connected nonrotatably to a different power takeoff element.
2. Description of the Related Art
Multi-disk clutch arrangements of this type are frequently used as clutches for so-called load-switching transmissions, in which the path along which the torque is transmitted alternates between two different transmission input shafts, which are usually concentric to each other. To avoid interruptions in the tractive force as effectively as possible during the performance of the switching or clutching operations, operating phases with slip occur, during which a considerable amount of frictional heat is generated in the clutch arrangement.
The task of the present invention is to design a multi-disk clutch arrangement in such a way that the heat generated during the operation of the clutch can be dissipated effectively.
According to a first aspect of the present invention, a clutch cooling arrangement, through which a coolant can flow, is installed adjacent to the clutch arrangement.
By providing a cooling arrangement, through which a coolant flows, in the area adjacent to the clutch arrangement, it is ensured that heat will not concentrate, and that the heat caused essentially by friction can be carried rapidly away. The areas subjected to severe thermal stress are therefore relieved, which means that the overall service life of a clutch arrangement of this type can be prolonged.
It is possible, for example, for the cooling arrangement to be installed so that it surrounds at least a certain area of the housing radially on the outside.
So that various components of the system can be made to do double duty, it is proposed that the cooling arrangement form a part of an electric machine designed to introduce torque and/or to recover electrical energy. Heat which must be carried away is also generated during operations with systems of this type, which are also known as starter/generator units, and which are able to supply the torque required to start an internal combustion engine and to supply supplemental torque which can be used during the operation of the engine, and which can then convert kinetic energy into electrical energy once the internal combustion engine is running. The cooling arrangement to be provided according to the invention can therefore be used both to carry away heat from the area of the clutch arrangement and also to carry away heat from the area of the electric machine.
It is possible, for example, for the electric machine to have a stator area, supported on a carrier and surrounding the axis of rotation, and a rotor area, which is connected to the housing arrangement for rotation in common and rotates with respect to the stator area, and for the cooling arrangement to form at least a part of the carrier of the stator area.
So that a good heat-conducting connection with both the electric machine and the clutch arrangement can be obtained, it is possible in accordance with another advantageous aspect of the invention to provide a rotor interaction area, which surrounds a stator interaction area radially on the outside.
The carrier can include a ring-shaped body with a U-shaped cross section, where the rotor interaction area and the stator interaction area are surrounded essentially by the U-shaped profile of the ring-shaped body.
To improve the effectiveness with which the heat is dissipated even more, it is proposed that the cooling arrangement have a preferably rib-like surface structure on the side facing the housing arrangement.
The heat generated in the area of the thermally stressed components, that is, in particular in the area of the opposing support arrangement, can be dissipated even more effectively by designing the opposing support arrangements of the two clutch areas situated next to each other in the direction of the axis of rotation so that they are formed essentially by ring-shaped opposing support areas, in which at least one channel-like air pass-through opening is provided.
According to another aspect of the present invention, the opposing support arrangements of the two clutch areas situated next to each other in the direction of the axis of rotation are formed essentially by ring-shaped opposing support areas, in which at least one channel-like air pass-through opening is provided.
So that centrifugal force can be used efficiently to circulate the air, it is proposed that the minimum of one air pass-through opening be open to a radially interior side of the ring-shaped opposing support area. Another advantage of this arrangement is that the surfaces available for frictional interaction, which usually extend in the axial direction, and are not affected by any openings.
Other objects and features of the present invention will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. It should be further understood that the drawings are not necessarily drawn to scale and that, unless otherwise indicated, they are merely intended to conceptually illustrate the structures and procedures described herein.